arXiv subjects

Gang Lü

Publications and source records attributed to Gang Lü.

24 records · Page 2Linked to original sources

arXiv2016

$CP$ violation for $B^+_{c}\rightarrow D_{(s)}^+π^+π^-$ in Perturbative QCD

In the perturbative QCD (PQCD) approach we study the direct $CP$ violation in $B^+_{c}\rightarrow D_{(s)}^+ρ^0(ω) \rightarrow D_{(s)}^+π^+π^-$ via the $ρ-ω$ mixing mechanism. We find that the $CP$ violation can be enhanced by $ρ-ω$ mixing when the invariant masses of the $π^+π^-$ pairs are in the vicinity of the $ω$ resonance. For the decay process $B^+_{c}\rightarrow D^+ρ^0(ω) \rightarrow D^+π^+π^-$, the maximum $CP$ violation can reach 7.5 {\%}.

hep-ph↗

arXiv2015

Theoretical analysis of direct $CP$ violation and differential decay width in $D^\pm\to π^\pm π^+π^-$ in phase space around the resonances $ρ^0(770)$ and $f_0(500)$

We perform a theoretical study on direct $CP$ violation in $D^\pm\to π^\pm π^+π^-$ in phase space around the intermediate states $ρ^0(770)$ and $f_0(500)$. The possible interference between the amplitudes corresponding to the two resonances is taken into account, and the relative strong phase of the two amplitudes is treated as a free parameter. Our analysis shows that by properly chosen the strong phase, both the $CP$ violation strength and differential decay width accommodate to the experimental results.

hep-ph↗

arXiv2014

$CP$ violation for $B^{0}\rightarrow ρ^{0}(ω)ρ^{0}(ω) \rightarrow π^+π^-π^+π^-$ in QCD factorization

In the QCD factorization (QCDF) approach we study the direct $CP$ violation in $\bar{B}^{0}\rightarrowρ^0(ω)ρ^0(ω)\rightarrowπ^+π^-π^+π^-$ via the $ρ-ω$ mixing mechanism. We find that the $CP$ violation can be enhanced by double $ρ-ω$ mixing when the masses of the $π^+π^-$ pairs are in the vicinity of the $ω$ resonance, and the maximum $CP$ violation can reach 28{\%}. We also compare the results from the naive factorization and the QCD factorization.

hep-ph↗

arXiv2013

Production of charged $ρ$ meson in bottom hadron charmed decays and the effect of the finite width correction of the $ρ$ meson

We calculate the branching ratio of a bottom hadron decaying into a charmed hadron and a charged $ρ$ meson within the QCD factorization approach. We consider the effect of the finite width correction of the $ρ$ meson. Our numerical calculation shows an obvious correction because of this effect. We find that the finite width effect of the $ρ$ meson reduces the branching ratios by about 9% to 11% for bottom meson decay channels: $B^+\to\bar{D^0}ρ^+$, $B^0\to D^-ρ^+$, and $B^0_s\to D^-_sρ^+$, and increases the branching ratio by about 10% for $Λ_b^0\toΛ_c^+ρ^-$.

hep-ph↗

arXiv2011

QCD factorization for $Λ_b^0\toΛ_c^+π^-$

We prove that in the limit $m_b, m_c\to\infty$ with $m_c/m_b$ fixed, factorization holds at order $α_s$ for the decay $Λ_b^0\toΛ_c^+π^-$. This proof is done in the infinite-momentum frame in which the momenta of $π$, $Λ_c$, and $Λ_b$ go to infinity. Our result is renormalization scale and scheme independent at $\mathcal{O}(α_s)$. This is the same as QCD factorization for $B \to D π$.

hep-ph↗

arXiv2010

Direct CP violation for $\bar{B}_{s}^{0}\to K^{0}π^{+}π^{-}$ decay in QCD factorization

In the framework of QCD factorization, based on the first order of isospin violation, we study direct CP violation in the decay of $\bar{B}_{s}^{0} \to K^{0}ρ^{0}(ω)\to K^{0}π^{+}π^{-}$ including the effect of $ρ-ω$ mixing. We find that the CP violating asymmetry is large via $ρ-ω$ mixing mechanism when the invariant mass of the $π^{+}π^{-}$ pair is in the vicinity of the $ω$ resonance. For the decay of $\bar{B}_{s}^{0} \to K^{0}ρ^{0}(ω)\to K^{0}π^{+}π^{-}$, the maximum CP violating asymmetries can reach about 46%. We also discuss the possibility to observe the predicted CP violating asymmetries at the LHC.

hep-ph↗